Supreme Court has ruled on Same-Sex benefits

The high court ruled against retroactive Canada Pension Plan survivor benefits to gay couples extending all the way back to 1985, but it did allow for payment of 12 months of retroactive compensation.
A class action suit had been filed alleging that legislation discriminated against gay couples by not allowing them CPP Survivor Benefits, and thus their equity rights had been violated.
The costs of rewarding retroactive CPP survivor benefits are expected to be about $100 million, which the article says 'is just a drop in the bucket for the gigantic pension plan'.
There is more detail about the evolution of the case in the article.